Fangs that can pierce through the armor of a towering tartarian, to destroy it in seconds?
Anyway, I wasn't just guessing here.
In another game I've been battling hundreds of vampires with squads of Niefel Jarls, and they've hardly been scratched at all. I assumed from the performance, that it was because they were resisting the effect, rendering the vampires somewhat neuter.
Oh well, it's not like I've never lost a tartarian.
